Influence of gas penetrans on polyethylene crystallinity observed by low field NMR

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22340%2F23%3A43928590" target="_blank" >RIV/60461373:22340/23:43928590 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0142941823002544?via%3Dihub" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0142941823002544?via%3Dihub</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.polymertesting.2023.108174" target="_blank" >10.1016/j.polymertesting.2023.108174</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Influence of gas penetrans on polyethylene crystallinity observed by low field NMR

Popis výsledku v původním jazyce

Polyethylene (PE) has a broad range of applications requiring rather different grades of used material differing also by their inner structure. PE inner structure contains two easily distinguishable phases: crystalline and amorphous. In this paper, we present a simple method of measurement of crystallinity (crystal content in sample) using low-field nuclear magnetic resonance. Moreover, we measured the crystallinity under different pressures of organic penetrant in order to observe sorption influence on inner PE structure. We confirm the broadly accepted fact that the penetrant sorbs into the amorphous phase. However, our results, measured at 35 degrees C, show that also the crystal phase is influenced by the sorption and with increasing pressure of organic penetrant (and so with increasing penetrated amount) the crystallinity of the sample decreases. We performed polymer-gas equilibrium measurements in ethylene and propylene environment to simulate catalytic polymerization conditions. We observed decrease in the crystallinity up to 9.5% at 30 bar ethylene pressure and 6.2% decrease at 11 bar propylene pressure. We propose, that the sorption process, even when induced by low soluble ethylene, decreases the crystallinity of the PE by various mechanisms.

Název v anglickém jazyce

Influence of gas penetrans on polyethylene crystallinity observed by low field NMR

Popis výsledku anglicky

Polyethylene (PE) has a broad range of applications requiring rather different grades of used material differing also by their inner structure. PE inner structure contains two easily distinguishable phases: crystalline and amorphous. In this paper, we present a simple method of measurement of crystallinity (crystal content in sample) using low-field nuclear magnetic resonance. Moreover, we measured the crystallinity under different pressures of organic penetrant in order to observe sorption influence on inner PE structure. We confirm the broadly accepted fact that the penetrant sorbs into the amorphous phase. However, our results, measured at 35 degrees C, show that also the crystal phase is influenced by the sorption and with increasing pressure of organic penetrant (and so with increasing penetrated amount) the crystallinity of the sample decreases. We performed polymer-gas equilibrium measurements in ethylene and propylene environment to simulate catalytic polymerization conditions. We observed decrease in the crystallinity up to 9.5% at 30 bar ethylene pressure and 6.2% decrease at 11 bar propylene pressure. We propose, that the sorption process, even when induced by low soluble ethylene, decreases the crystallinity of the PE by various mechanisms.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20401 - Chemical engineering (plants, products)

Projekt

<a href="/cs/project/GA19-22834S" target="_blank" >GA19-22834S: Částicové modely polymerních latexů pro realistická časová a prostorová měřítka</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2023

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

POLYMER TESTING

ISSN

0142-9418

e-ISSN

1873-2348

Svazek periodika

127

Číslo periodika v rámci svazku

OCT 2023

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

9

Strana od-do

—

Kód UT WoS článku

001070598300001

EID výsledku v databázi Scopus

2-s2.0-85169011087